Viper, the Netherdrake, is a devastating Agility-based ranged carry, lane dominator, and anti-mage in DotA 1. Notorious for his ability to shut down opponents during the laning phase, Viper excels at punishing single targets with corrosive damage over time and movement speed slows. While he lacks natural escape mechanics, his balanced attribute distribution and passive defensive shell make him exceptionally durable. His kit is designed to systematically wear down enemies, scaling his offensive power dynamically based on how close his targets are to death.
2. Base Stats & Attributes
Hero Attributes
| Attribute |
Base Value |
Growth (per level) |
| Strength |
21 |
+2.4 |
| Agility |
21 |
+2.5 |
| Intelligence |
15 |
+1.8 |
Statistics & Mechanics
| Statistic |
Value |
Mechanic |
Value |
| Damage |
46-48 |
Base HP Regen |
0.25/s |
| HP |
620 |
HP Regen |
+2.35/s |
| MP |
230 |
MP Regen |
+0.76/s |
| Armor |
1 |
Turn Rate |
0.5 |
| Move Speed |
275 |
Base Attack Time (BAT) |
1.7 |
| Attack Range |
575 (missile speed: 1200) |
Attack Animations |
0.33 / 1 |
3. Hero Skills Breakdown
1. Poison Attack
Intensifies Viper's venom, resulting in a deadly poison that slows the target's movement speed. With each passing second of affliction, the target sustains magical damage that scales dynamically according to their missing health.
- Damage Type: Magical
- Debuff Duration: 3 seconds
- Mechanic: Manual activation allows "orb walking" to harass enemies in lane without pulling creep aggro.
| Level |
Movement Speed Slow |
Missing Health Damage Multiplier |
Cooldown |
Manacost |
| 1 |
10% |
0.50 damage per % missing HP |
0 sec |
40 |
| 2 |
20% |
0.75 damage per % missing HP |
0 sec |
35 |
| 3 |
30% |
1.00 damage per % missing HP |
0 sec |
30 |
| 4 |
40% |
1.25 damage per % missing HP |
0 sec |
25 |
2. Nethertoxin
Viper releases a pool of Nethertoxin at the targeted ground area. Enemy units standing within this acidic zone sustain magical damage each second, suffer from amplified incoming magical damage, and have their passive abilities entirely disabled.
- Damage Type: Magical
- Effect Area: Targeted ground AoE
- Debuff Duration: 8 seconds
- Unique Utility: Applies Break (completely disables passive abilities)
- Stacking Rule: Debuff effects from multiple instances of Nethertoxin do not stack on a single target.
| Level |
Damage per Second (DPS) |
Magical Damage Amplification |
Cooldown |
Manacost |
| 1 |
30 |
10% |
14 sec |
70 |
| 2 |
45 |
15% |
14 sec |
80 |
| 3 |
60 |
20% |
14 sec |
90 |
| 4 |
75 |
25% |
14 sec |
100 |
3. Corrosive Skin
Viper exudes an infectious toxin across his scales. Any enemy unit bold enough to attack Viper directly will have their attack speed reduced and suffer poison damage over time. The biological properties of this acidic defense also bolster Viper's natural resistance to magical spells.
- Damage Type: Magical
- Trigger Condition: Automatically applies to any unit that damages Viper with physical or spell damage.
- Debuff Duration: 4 seconds
| Level |
Damage per Second (DPS) |
Attack Speed Slow |
Passive Magic Resistance |
Cooldown |
Manacost |
| 1 |
12 |
8% |
10% |
Passive |
0 |
| 2 |
18 |
16% |
15% |
Passive |
0 |
| 3 |
24 |
24% |
20% |
Passive |
0 |
| 4 |
30 |
32% |
25% |
Passive |
0 |
4. Viper Strike
Strikes a target unit with a vicious bite from a distance, drastically reducing both their movement and attack speeds while dealing immense magical poison damage over time.
- Damage Type: Magical
- Debuff Duration: 5 seconds
- Aghanim's Scepter Upgrade: Drastically reduces the ability's cooldown and increases the cast range.
| Level |
Damage per Second (DPS) |
Attack & Move Speed Slow |
Standard Cooldown |
Scepter Cooldown |
Standard Cast Range |
Scepter Cast Range |
Manacost |
| 1 |
80 |
40% |
50 sec |
10 sec |
500 |
900 |
125 |
| 2 |
120 |
60% |
40 sec |
10 sec |
500 |
900 |
175 |
| 3 |
160 |
80% |
30 sec |
10 sec |
500 |
900 |
250 |
4. Item Build Guide
| Phase |
Recommended Items |
Strategic Purpose |
| Early Game |
Power Treads, Wraith Band, Magic Wand |
Power Treads address Viper's slow 275 base movement speed while providing stats and attack speed. Wraith Band pads his early HP and physical damage, and Magic Wand handles crucial resource recovery. |
| Core Items |
Mekansm, Aghanim's Scepter, Black King Bar (BKB) |
Mekansm turns Viper into a team-fight fortress, converting his lane dominance into early pushes. Aghanim's Scepter makes his ultimate spammable (10-second cooldown), while BKB ensures he can walk through fights uninterrupted. |
| Late Game |
Eye of Skadi, Butterfly, Heart of Tarrasque |
Eye of Skadi stacks slow effects and provides massive all-around attributes. Butterfly leverages his Agility scaling for physical damage and evasion, and Heart of Tarrasque maximizes his durability to make Corrosive Skin highly punishing. |
5. Quick Gameplay Tips
- The Break Area Control: Nethertoxin is your most powerful utility tool in team fights. Because it applies a complete Break effect, always cast it directly underneath heroes that rely heavily on passives (such as Mortred's Blur, Huskar's Berserker's Blood, or Bristleback's Bristleback). Disabling these passives makes them incredibly soft and easy for your team to tear down.
- Orb Walking in Lane: To completely shut down your lane opponent, use manual casting on Poison Attack (press your hotkey, then left-click the enemy hero). In DotA 1 mechanics, this is considered a spell cast rather than a physical attack, allowing you to hit the enemy repeatedly without drawing any aggression from nearby lane creeps.
- The Scepter Snipe Engine: Once you acquire Aghanim's Scepter, Viper Strike becomes an initiation and chasing tool with an absurd 900 cast range and a 10-second cooldown. Use it to catch out-of-position enemies from nearly screen-distance away, crippling their movement speed by up to 80% so your team can easily close the gap.